吡咯, 噻酚和呋喃的情况就是这样.Such is the case in pyrrole, thiophene, and furan.研究结果表明关键步骤为原料 4- 甲基 -2, 3- 呋喃二酮的合成.It'shows that the key step is the synthesis of 4 - methyl - dihydro - furan - 2 , 3 - dione.用糠醇和糠醛缩聚制备了新型呋喃树脂.A n...
提出了一种干柱层析法 分离提纯 试剂对氨基偶氮苯的新方法.A new method for separating and purifying p - AAB ( p - aminoazobenzene ) by dry - column chromatography is developed.偶氮苯侧链液晶聚合物.Azobenzene side - chain liquid crystalline.必须通过偶氮,(苯)酚类,有机氯试剂,...
Add 20 mg. of diatomaceous earth filter aid per liter of solution.对每升溶液加入20毫克硅藻土助滤剂.Acid - washed, flux - calcinated diatomaceous earth is often used.通常使用酸洗的, 通量煅烧硅藻土.Diatomaceous earths are the skeletal remains of the t...
50年的经验使得他在款式上有自己的独到见解。His 50 years of experience have given him strong convictions about style.有些款式特别衬人，很快就成了经典。Some styles are so flattering that they instantly become classics.她会教你如何搭配款式和颜色。She'll show you how to ...